The present invention relates to a structure of a suspension mounting portion and an assembling method of the suspension mounting portion, and particularly to a structure of a suspension mounting portion of a vehicle such as an automotive vehicle and the like and an assembling method of the suspension mounting portion.
In general, the structure of the suspension mounting portion of the automotive vehicle and the like requires accurately, positioning a suspension system assembled therein and having sufficient strength and rigidity. Then, a structure suitable for manufacturing processes in a mass production line is also required for the structure of the suspension mounting portion mentioned above, and it is of course necessary to satisfy a requirement in view of a cost, a weight and the like.
In accordance with considerations of the inventors of the present invention, there is exemplified a structure of a suspension mounting portion shown in FIGS. 8 and 9.
In FIGS. 8 and 9, reference numeral 101 denotes a frame member in a longitudinal direction of a vehicle, that is, a rear side member having a main cross section formed in a hat shape.
The rear side member 101 is structured such that a flange 101a in an upper edge thereof is joined to a lower surface of a rear floor panel 102. On the contrary, in a side portion of the vehicle, the upper edge flange 101a is joined to an end portion of a wheel house inner 103 corresponding to a frame member in a rear side portion of the vehicle together with the rear floor panel 102. As mentioned above, a closed cross sectional portion 104 is formed by the rear side member 101 and the floor panel 102.
Reference numeral 105 denotes a suspension bolt which is fixed to the closed cross sectional portion 104 and mounts a suspension bracket (not shown) to a lower side of the closed cross sectional portion 104. Amounting portion 110 is provided in a center portion of the suspension bolt 105.
Reference numeral 113 denotes a lower bracket having a first mounting surface 106 for mounting the suspension bolt 105. The lower bracket 113 is structured such that peripheral edge flanges 113a thereof are joined to an outer side wall 101b and a lower surface 101c of the rear side member 101.
Reference numeral 114 denotes an upper bracket having a second mounting surface 107 for mounting an upper end portion of the suspension bolt 105. The upper bracket 114 is structured such that peripheral edge flanges 114a thereof are joined to a reinforce 108 inserted into the rear side member 101 so as to be abutted on a bottom wall 101A of the rear side member 101 along an inner side thereof.
In the structure mentioned above, particular assembling process of the suspension bolt 105 are as follows.
At first, the suspension bolt 105 is inserted into a bolt insertion hole 118 of the lower bracket 113 and the mounting portion 110 of the suspension bolt 105 is fixed to a first mounting surface 106 of the lower bracket 113 by means of a welding P such as a projection welding and the like.
In the meantime, the reinforce 108 and the upper bracket 114 are sub-assembled.
Next, the rear side member 101 and the lower bracket 113 are joined to each other while inserting the upper portion of the suspension bolt 105 from a bolt insertion hole 115 provided in the rear side member 101.
Next, the reinforce 108 and the upper bracket 114 which are integrally formed in accordance with the sub-assembly are joined to the rear side member 101 while successively inserting the upper portion of the suspension bolt 105 into a bolt insertion hole 116 provided in the reinforce 108 and a bolt insertion hole 119 provided in the upper bracket 114.
Next, the upper end portion of the suspension bolt 105 is fixed to the second mounting surface 107 provided in the upper bracket 114 by means of the projection welding P or the like.
As in the manner mentioned above, the suspension bracket is fixed to the lower side of the closed cross sectional portion 104 by the suspension bolt 105 extending and fixed through the first mounting surface 106 and the second mounting surface 107.
However, even in accordance with the structure mentioned above, the structure is complex, a number of the assembling processes is excessive and a cost therefore is increased.
Further, since the number of the parts is excessive such as the lower bracket 13, the upper bracket 14 and the like, a man-hour for managing the parts and a weight becomes much.
Accordingly, an object of the present invention is to provide a structure of a suspension mounting portion which can achieve both of making a weight of a vehicle light and improving a supporting rigidity of a suspension system, and an assembling method thereof.
The structure of the suspension mounting portion in accordance with the present invention is provided with a side member which extends in a longitudinal direction of a vehicle and is connected to a lower surface of a floor panel, a closed cross sectional portion which is formed by use of the floor panel and the side member, a suspension bolt which mounts a suspension system constituting element to a lower side of the closed cross sectional portion, a first mounting surface which is provided by use of a recess portion formed on a bottom wall of the side member and mounts the suspension bolt, a reinforce which is provided to an inner portion of the closed cross sectional portion, and a second mounting surface which is provided to the reinforce and mounts the suspension bolt. The suspension system constituting element is mounted to the lower side of the closed cross sectional portion by use of the suspension bolt fixed through the first mounting surface and the second mounting surface.
On the contrary, an assembling method of a suspension mounting portion in accordance with the present invention comprises steps of inserting an end portion of a suspension bolt to a bolt insertion hole formed on a first mounting surface of a side member, fixing the suspension bolt to the first mounting surface, inserting the other end portion of the suspension bolt to a bolt insertion hole provided in a reinforce, fitting the reinforce to an inner side of the side member, and fixing the other end portion of the suspension bolt to a second mounting surface provided in the reinforce. In this case, the structure is made such that the side member extends in a longitudinal direction of the vehicle and is connected to the lower surface of the floor panel, and the first mounting surface is provided by use of a recess portion of the side member. Then, a suspension system constituting element is mounted to a closed cross sectional portion formed by use of the floor panel and the side member, by means of the suspension bolt fixed through the first mounting surface and the second mounting surface.